Transcatheter Prosthetic Heart Valve Delivery System with Recapturing Feature

ABSTRACT

A delivery system for percutaneously deploying a stented prosthetic heart valve. The system includes a delivery capsule and a recapture assembly. The capsule is configured to compressively retain the prosthesis. The recapture assembly includes a frame and sleeve attached to the frame. The recapture assembly is transitionable from a compressed arrangement to an expanded arrangement with a distally increasing diameter.

BACKGROUND

The present disclosure relates to systems and methods for percutaneousimplantation of a heart valve prosthesis. More particularly, it relatesto systems and methods for transcatheter implantation of a stentedprosthetic heart valve, including partial deployment, recapturing, andrepositioning of the prosthesis at the implantation site.

Diseased or otherwise deficient heart valves can be repaired or replacedwith an implanted prosthetic heart valve. Conventionally, heart valvereplacement surgery is an open-heart procedure conducted under generalanesthesia, during which the heart is stopped and blood flow iscontrolled by a heart-lung bypass machine. Traditional open surgeryinflicts significant patient trauma and discomfort, and exposes thepatient to a number of potential risks, such as infection, stroke, renalfailure, and adverse effects associated with the use of the heart-lungbypass machine, for example.

Due to the drawbacks of open-heart surgical procedures, there has beenan increased interest in minimally invasive and percutaneous replacementof cardiac valves. With these percutaneous transcatheter (ortransluminal) techniques, a valve prosthesis is compacted for deliveryin a catheter and then advanced, for example, through an opening in thefemoral artery and through the descending aorta to the heart, where theprosthesis is then deployed in the annulus of the valve to be repaired(e.g., the aortic valve annulus). Although transcatheter techniques haveattained widespread acceptance with respect to the delivery ofconventional stents to restore vessel patency, only mixed results havebeen realized with percutaneous delivery of a relatively more complexprosthetic heart valve.

Various types and configurations of prosthetic heart valves areavailable for percutaneous valve procedures, and continue to be refined.The actual shape and configuration of any particular prosthetic heartvalve is dependent to some extent upon the native shape and size of thevalve being repaired (i.e., mitral valve, tricuspid valve, aortic valve,or pulmonary valve). In general, prosthetic heart valve designs attemptto replicate the functions of the valve being replaced and thus willinclude valve leaflet-like structures. With a bioprosthesesconstruction, the replacement valve may include a valved vein segmentthat is mounted in some manner within an expandable stent frame to makea valved stent (or “stented prosthetic heart valve”). For manypercutaneous delivery and implantation systems, the stent frame of thevalved stent is made of a self-expanding material and construction. Withthese systems, the valved stent is crimped down to a desired size andheld in that compressed arrangement within an outer sheath, for example.Retracting the sheath from the valved stent allows the stent toself-expand to a larger diameter, such as when the valved stent is in adesired position within a patient. In other percutaneous implantationsystems, the valved stent can be initially provided in an expanded oruncrimped condition, then crimped or compressed on a balloon portion ofcatheter until it is as close to the diameter of the catheter aspossible. Once delivered to the implantation site, the balloon ininflated to deploy the prosthesis. With either of these types ofpercutaneous stent delivery systems, conventional sewing of theprosthetic heart valve to the patient's native tissue is typically notnecessary.

It is imperative that the stented prosthetic heart valve be accuratelylocated relative to the native annulus immediately prior to fulldeployment from the catheter as successful implantation requires theprosthetic heart valve intimately lodge and seal against the nativeannulus. If the prosthesis is incorrectly positioned relative to thenative annulus, serious complications can result as the deployed devicecan leak and may even dislodge from the native valve implantation site.As a point of reference, this same concern does not arise in the contextof other vascular stents; with these procedures, if the target site is“missed,” another stent is simply deployed to “make-up” the difference.

While imaging technology can be employed as part of the implantationprocedure to assist a clinician in better evaluating a location of thetranscatheter prosthetic heart valve immediately prior to deployment, inmany instances, this evaluation alone is insufficient. Instead,clinicians desire the ability to partially deploy the prosthesis,evaluate a position relative to the native annulus, and reposition theprosthesis prior to full deployment if deemed necessary. Repositioning,in some instances, can require the prosthesis first be re-compressed andre-located back within the outer delivery sheath. Stated otherwise, thepartially deployed stented prosthetic heart valve can be “recaptured” bythe delivery system, and in particular within the outer sheath. While,in theory, the recapturing of a partially deployed stented prostheticheart valve is straight forward, in actual practice, the constraintspresented by the implantation site and the stented heart valve itselfrender the technique exceedingly difficult.

For example, the stented heart valve is purposefully designed to rigidlyresist collapsing forces once deployed to properly anchor itself in theanatomy of the heart. Thus, whatever tooling is employed to force apartially-deployed segment of the prosthesis back to a collapsedarrangement must be capable of exerting a significant radial force.Conversely, however, the tooling cannot be overly rigid to avoiddamaging the transcatheter heart valve as part of a recapturingprocedure. Along these same lines, the aortic arch must be traversed,necessitating that the delivery system provide sufficient articulationattributes. Unfortunately, existing delivery systems do not consider,let alone optimally address, these and other issues.

As mentioned above, an outer sheath or catheter is conventionallyemployed to deliver a self-deploying vascular stent. Applying this sametechnique for the delivery of a self-deploying stented prosthetic heartvalve, the high radial expansion force associated with the prosthesis isnot problematic for complete deployment as the outer sheath is simplyretracted in tension to allow the prosthetic heart valve to deploy. Werethe conventional delivery system operated to only partially withdraw theouter sheath relative to the prosthesis, only the so-exposed distalregion of the prosthetic would expand while the proximal region remainscoupled to the delivery system. In theory, the outer sheath could simplybe advanced distally to recapture the expanded region. Unfortunately,with conventional sheath configurations, attempting to compress theexpanded region of the stented prosthetic heart valve by distallysliding the sheath is unlikely to be successful. The conventionaldelivery sheath cannot readily overcome the radial force of the expandedregion of the prosthesis because, in effect, the sheath is placed intocompression and will collapse due at least in part to the abrupt edge ofthe sheath being unable to cleanly slide over the expanded region of theprosthesis. This effect is illustrated in a simplified form in FIGS.1A-1C. Prior to deployment (FIG. 1A), the stented prosthetic heart valveP is constrained within, and supports, the sheath S. With deployment(FIG. 1B), the sheath S is distally retracted, and the prosthesis Ppartially deploys. Where an attempt made to “recapture” the prosthesis Pby distally sliding the sheath (FIG. 1C), a leading end E of the sheathS abruptly abuts against the enlarged diameter of the prosthesis P, suchthat the distal end E cannot readily slide over the prosthesis P.Further, the sheath S is no longer internally supported and the radiallyexpanded bias of the prosthesis P causes the sheath S to buckle orcollapse.

In light of the above, a need exists for a stented transcatheterprosthetic heart valve delivery system and method that satisfies theconstraints associated with heart valve implantation and permits partialdeployment and recapturing of the prosthesis.

SUMMARY

Some aspects in accordance with principles of the present disclosurerelate to a delivery system for percutaneously deploying a stentedprosthetic heart valve. The prosthetic heart valve is radiallyself-expandable from a compressed arrangement to a natural arrangement.The delivery system includes an inner shaft assembly, a delivery sheathcapsule, and a recapture assembly. The inner shaft assembly includes anintermediate region providing a coupling structure configured toselectively engage a stented prosthetic heart valve. The delivery sheathcapsule is slidably disposed over the inner shaft assembly and isconfigured to compressively retain a stented prosthetic heart valveengaged with the coupling structure. The recapture assembly is slidablydisposed over the inner shaft assembly and includes a recapture frameand sleeve coupled to the frame. The frame is transitionable from acompressed arrangement to an expanded arrangement in which the frameforms a funnel shape having a distally increasing diameter as thedelivery sheath capsule is retracted. With this construction, thedelivery system is configured to provide a loaded state in which thecapsule compressively retains the stented prosthetic heart valve overthe inner shaft assembly and the recapture assembly is longitudinallydisplaced from the prosthetic heart valve. During use, the recaptureassembly can be employed to facilitate sliding of the recapture frameover a partially deployed region of the prosthetic heart valve as partof a recapturing operation. The recapture frame is configured to providea columnar strength to the recapture assembly, with the sleeve providinga surface to engage and slide over a partially deployed prosthetic heartvalve.

Yet other aspects in accordance with principles of the presentdisclosure relate to a device for repairing a heart valve of a patient.The device includes a delivery system and a prosthetic heart valve. Thedelivery system includes the inner shaft assembly, the delivery sheathcapsule, and the recapture assembly, including the recapture frame andsleeve, as described above. The prosthetic heart valve has a stent frameand a valve structure forming at least two valve leaflets attached tothe stent frame. With this construction, the prosthetic heart valve isself-expandable from a compressed arrangement to a natural arrangement.With this construction, the device is configured to be transitionablebetween a loaded state, a partially deployed state, and a recapturingstate. In the loaded state, the prosthetic heart valve is coupled to theintermediate region of the inner shaft assembly, with the capsulecompressively retaining the prosthetic heart valve in the compressedarrangement. Further, the recapture assembly is longitudinally spacedfrom the prosthetic heart valve. In the partially deployed state, thecapsule is at least partially withdrawn from the prosthetic heart valvesuch that a distal region of the prosthetic heart valve is exposedrelative to the capsule and self-expands. In the recapturing state, therecapture assembly is positioned distal the capsule and along the distalexposed region of the prosthetic heart valve, causing the recaptureframe to expand toward the expanded condition to recapture theprosthetic heart valve.

Yet other aspects in accordance with principles of the presentdisclosure relate to a method of deploying a stented prosthetic heartvalve to an implantation site. The method includes receiving a deliverysystem loaded with a radially expandable prosthetic heart valve having astent frame to which a valve structure is attached. The delivery systemincludes a delivery sheath capsule compressively containing theprosthetic heart valve in a compressed arrangement over an inner shaftassembly in a loaded state, as well as a recapture assembly including aframe and sleeve slidably disposed over the inner shaft assembly. In theloaded state, the recapture assembly is longitudinally spaced from theprosthetic heart valve. The prosthetic heart valve is delivered, in thecompressed arrangement, through a bodily lumen of the patient and to theimplantation site via the delivery system in the loaded state. Thecapsule is proximally retracted relative to the prosthetic heart valvesuch that a distal region of the prosthetic heart valve is exposeddistal the capsule. The exposed, distal region self-expands toward adeployed arrangement. A position of the partially deployed prostheticheart valve relative to the implantation site is evaluated. Based uponthe evaluation, the recapture assembly is distally advanced relative tothe prosthetic heart valve such that the recapture assembly is distallyadvanced over the prosthetic heart valve.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1C are simplified side views illustrating deficiencies ofexisting stent delivery sheaths or catheters to effectuate recapture ofa partially deployed stented prosthetic heart valve;

FIG. 2 is an exploded, perspective view of a delivery system inaccordance with principles of the present disclosure and useful forpercutaneously delivering a stented prosthetic heart valve to a heartvalve implantation site;

FIG. 3 is a side view of the recapture assembly of FIG. 2 in a partiallyexpanded condition; and

FIGS. 4A-4E are simplified, cross-sectional views illustrating use ofthe delivery system of FIG. 2 in implanting a stented prosthetic heartvalve, including partial deployment and repositioning thereof.

DETAILED DESCRIPTION

Current transcatheter heart valve delivery systems do not have thecapability of transcatheter valve repositioning in the antegrade orretrograde directions after deployment. The delivery systems of thepresent disclosure overcome these problems, and permit the clinician topartially deploy the prosthetic heart valve, and prior to release,reposition or recapture and remove it. In general terms, the systemfunctions by providing a recapture assembly having a recapture frame andsleeve that serves as a transition between the delivery sheath capsuleand an expanded region of a partially deployed prosthesis to effectuaterecapturing of the partially deployed prosthetic heart valve.

As referred to herein, the prosthetic heart valve as used in accordancewith the various systems, devices, and methods of the present disclosuremay include a wide variety of different configurations, such as abioprosthetic heart valve having tissue leaflets or a synthetic heartvalve having a polymeric, metallic, or tissue-engineered leaflets, andcan be specifically configured for replacing any heart valve. Thus, theprosthetic heart valve useful with the systems, devices, and methods ofthe present disclosure can be generally used for replacement of a nativeaortic, mitral, pulmonic, or tricuspid valves, for use as a venousvalve, or to replace a failed bioprosthesis, such as in the area of anaortic valve or mitral valve, for example.

In general terms, the prosthetic heart valves of the present disclosureinclude a stent or stent frame maintaining a valve structure (tissue orsynthetic), with the stent having a normal, expanded arrangement andcollapsible to a compressed arrangement for loading within the deliverysystem. The stent is normally constructed to self-deploy or self-expandwhen released from the delivery system. For example, the stentedprosthetic heart valve useful with the present disclosure can be aprosthetic valve sold under the trade name CoreValve® available fromMedtronic CoreValve, LLC. Other non-limiting examples of transcatheterheart valve prostheses useful with systems and methods of the presentdisclosure are described in U.S. Publication Nos. 2006/0265056;2007/0239266; and 2007/0239269, the teachings of each which areincorporated herein by reference. The stents or stent frames are supportstructures that comprise a number of struts or wire portions arrangedrelative to each other to provide a desired compressibility and strengthto the prosthetic heart valve. In general terms, the stents or stentframes of the present disclosure are generally tubular supportstructures having an internal area in which valve structure leafletswill be secured. The leaflets can be formed from a verity of materials,such as autologous tissue, xenograph material, or synthetics as areknown in the art. The leaflets may be provided as a homogenous,biological valve structure, such as porcine, bovine, or equine valves.Alternatively, the leaflets can be provided independent of one another(e.g., bovine, porcine or equine paracardial leaflets) and subsequentlyassembled to the support structure of the stent frame. In anotheralternative, the stent frame and leaflets can be fabricated at the sametime, such as may be accomplished using high-strength nano-manufacturedNiTi films produced at Advance BioProsthetic Surfaces (ABPS), forexample. The stent frame support structures are generally configured toaccommodate at least two (typically three) leaftlets; however,replacement prosthetic heart valves of the types described herein canincorporate more or less than three leaflets.

Some embodiments of the stent frames can be a series of wires or wiresegments arranged such that they are capable of self-transitioning froma collapsed arrangement to a normal, radially expanded arrangement. Insome constructions, a number of individual wires comprising the stentframe support structure can be formed of a metal or other material.These wires are arranged in such a way that the stent frame supportstructure allows for folding or compressing or crimping to thecompressed arrangement in which the internal diameter is smaller thanthe internal diameter when in the natural, expanded arrangement. In thecollapsed arrangement, such a stent frame support structure withattached valves can be mounted onto a delivery system. The stent framesupport structures are configured so that they can be changed to theirnatural, expanded arrangement when desired, such as by the relativemovement of one or more sheaths relative to a length of the stent frame.

The wires of these stent frame support structures in embodiments of thepresent disclosure can be formed from a shape memory material such as anickel titanium alloy (e.g., Nitinol™). With this material, the supportstructure is self-expandable from the compressed arrangement to thenatural, expanded arrangement, such as by the application of heat,energy, and the like, or by the removal of external forces (e.g.,compressive forces). This stent frame support structure can also becompressed and re-expanded multiple times without damaging the structureof the stent frame. In addition, the stent frame support structure ofsuch an embodiment may be laser-cut from a single piece of material ormay be assembled from a number of different components. For these typesof stent frame structures, one example of a delivery system that can beused includes a catheter with a retractable sheath that covers the stentframe until it is to be deployed, at which point the sheath can beretracted to allow the stent frame to self-expand. Further details ofsuch embodiments are discussed below.

With the above in mind, one embodiment of a transcatheter stentedprosthetic heart valve delivery system 30 is shown in FIG. 2. The system30 generally includes a recapture assembly 32, an inner shaft assembly34, a delivery sheath assembly 36, and a handle 38. Details on thevarious components are provided below. In general terms, however, thedelivery system 30 provides a loaded state in which a stented prostheticheart valve (not shown) is coupled to the inner shaft assembly 34 andcompressively retained within a capsule 40 of the delivery sheathassembly 36. The delivery sheath assembly 36 can be manipulated towithdraw the capsule 40 proximally from the prosthetic heart valve viaoperation of the handle 38, permitting the prosthesis to self-expand andrelease from the inner shaft assembly 34. Further, the handle 38 can beoperated to maneuver the recapture assembly 32 relative to the innershaft assembly 34 and the delivery sheath assembly 36 to position arecapture frame 42 and corresponding sleeve 50 (referenced generally) ofthe recapture assembly 32 distally beyond the capsule 40, permitting therecapture assembly 32 to self-expand, and over a partially deployedregion of the prosthetic heart valve to facilitate recapturing of theprosthesis within the capsule 40. As a point of reference, variousfeatures of the components 32-38 reflected in FIG. 2 and described belowcan be modified or replaced with differing structures and/or mechanisms.Thus, the present disclosure is in no way limited to the inner shaftassembly 34, the delivery sheath assembly 36, the handle 38, etc., asshown and described below. More generally, delivery systems inaccordance with the present disclosure provide features capable ofcompressively retaining a self-deploying, stented prosthetic heart valve(e.g., the capsule 40), a mechanism capable of effectuating release ordeployment of the prosthesis (e.g., retracting the capsule 40), and astructure (e.g., the recapture assembly 32) that promotes recapture.

The recapture assembly 32 includes the recapture frame 42 and the sleeve50 secured to the frame 42. The recapture assembly 32 also forms a lumen52 (referenced generally) sized to be slidably received over the innershaft assembly 34, with the recapture assembly 32 terminating at adistal end 54. With the one construction of FIG. 2, the recaptureassembly 32 is provided apart from the delivery sheath assembly 36, andis sized to be slidably received between the inner shaft assembly 34 andthe delivery sheath assembly 36. As such, an overall profile of deliverysystem 30 can be maintained without the need to accommodate a thicknessof the recapture assembly 32. Additionally, the recapture assembly 32can be a variety of different lengths, as compared with a length of thecapsule 40, such as half the length of the capsule 40, equal to thelength of capsule 40, greater than the length of capsule 40, etc.

The recapture frame 42 is configured to be radially expandable from thecompressed arrangement of FIG. 2 having a relatively small, relativelyuniform diameter to a radially expanded arrangement. In one embodiment,frame 42 is configured similar to the stent frame discussed above,wherein as forces are released on recapture frame 42 (e.g., as deliverysheath assembly 36 is retracted relative to the recapture assembly 32),a diameter of the distal end 54 is radially increased, as illustrated inFIG. 3. In one embodiment, frame 42 can be configured to create a funnelshape 56 with an increasing distal diameter so as to be configured torecapture a partially deployed prosthetic heart valve. As best shown inFIG. 3, in some embodiments the frame 42 includes a series of wires orwire segments capable of self-transitioning from the collapsedarrangement to the normal, radially expanded arrangement. In turn, theframe 42 creates a columnar strength within the recapture assembly 32.The funnel shape 56 can be formed as a characteristic of the frame 42,sleeve 50, radial strength of the delivery sheath assembly 36 and/orcombinations thereof.

In some constructions, a number of individual wires comprising a supportstructure of the recapture frame 42 can be formed of a metal or othermaterial. These wires are arranged in such a way that the recaptureframe support structure allows for folding or compressing or crimping tothe compressed arrangement in which the internal diameter is smallerthan the internal diameter when in the natural, expanded arrangement. Inthe collapsed arrangement, such a recapture frame support structure canbe mounted onto delivery system 30. The recapture frame supportstructures are configured so that they can be changed to their natural,expanded arrangement when desired, such as by the relative movement ofone or more sheaths relative to a length of the recapture frame 42.

The wires of these recapture frame support structures in embodiments ofthe present disclosure can be formed from a shape memory material suchas a nickel titanium alloy (e.g., Nitinol™). With this material, thesupport structure is self-expandable from the compressed arrangement tothe natural, expanded arrangement, such as by the application of heat,energy, and the like, or by the removal of external forces (e.g.,compressive forces). This recapture frame support structure can also becompressed and re-expanded multiple times without damaging the structureof the recapture frame 42. In addition, the recapture frame supportstructure of such an embodiment may be laser-cut from a single piece ofmaterial or may be assembled from a number of different components. Inany event, the recapture frame 42 can be embodied in a number ofdifferent ways, for example creating the wire structure as illustratedin FIG. 3. The wire structure can include an arrangement of wires and/orstruts arranged in various patterns that are configured to expand so asto recapture a prosthetic heart valve that has at least been partiallydeployed. In other embodiments, the frame 42 can include longitudinallyspaced rings that are coupled together through the sleeve 50. Thelongitudinally spaced rings can be configured to expand to a largerdiameter as compressive forces are released on the frame 42. In otherembodiments, the rings may include an undulating pattern. In stillfurther embodiments, the rings can be connected by longitudinal struts.

The sleeve 50 is a surgically safe, compliant polymeric material or filmpositioned on an interior side of the recapture frame 42 and, in theembodiment shown, wrapped around and folded over the frame 42 at distalend 54 of the recapture assembly 32 so as to create a smooth edge toprevent a frame of a prosthetic heart valve from becoming stuck on therecapture frame 42. However, it is not necessary for sleeve 50 to befolded over distal end 54. In other embodiments, sleeve 50 can bebonded, molded, overjacketed, etc. to frame 42. In one example, sleeve50 is formed of polyethylene terephthalate (PETE), although othermaterials can also be used. In the embodiment illustrated, sleeve 50 isfolded over and attached to frame 42 using a stitch 60, although inother embodiments the sleeve 50 is attached to frame 42 by other meansof attachment. With this construction, the sleeve 50 allows the frame 42to freely deflect or expand, as shown in the expanded condition of FIG.3. While the sleeve 50 can be elastically deformable, the sleeve 50 canalso provide resistance to continued deflection of the frame 42 beyond acertain level of deflection. Thus, in one embodiment the sleeve 50 cancontrol the length and angle of a taper defined by the funnel shape 56of frame 42 in the expanded arrangement. In any event, sleeve 50provides a surface to easily engage a prosthetic heart valve.

Returning to FIG. 2, the remaining components 34-38 of the deliverysystem 30 can assume a variety of forms appropriate for percutaneouslydelivering and deploying a stented self-expanding prosthetic heartvalve. For example, the inner shaft assembly 34 can have variousconstructions appropriate for supporting a stented prosthetic heartvalve within the capsule 40. In some embodiments, the inner shaftassembly 34 can include a retention member 100, an intermediate tube102, and a proximal tube 104. In general terms, the retention member 100can be akin to a plunger, and incorporates features for retaining thestented prosthetic heart valve within the capsule 40 as described below.The tube 102 connects the retention member 100 to the proximal tube 104,with the proximal tube 104, in turn, coupling the inner shaft assembly34 with the handle 38. The components 100-104 can combine to define acontinuous lumen 106 (referenced generally) sized to slidably receive anauxiliary component such as a guide wire (not shown).

The retention member 100 can include a tip 110, a support tube 112, anda hub 114. The tip 110 forms or defines a nose cone having a distallytapering outer surface adapted to promote atraumatic contact with bodilytissue. The tip 110 can be fixed or slidable relative to the supporttube 112. The support tube 112 extends proximally from the tip 110 andis configured to internally support a compressed, stented prostheticheart valve generally disposed thereover, and has a length and outerdiameter corresponding with dimensional attributes of the selectedprosthetic heart valve. The hub 114 is attached to the support tube 112opposite the tip 110 (e.g., an adhesive bond), and provides a couplingstructure 120 (referenced generally) configured to selectively capture acorresponding feature of the prosthetic heart valve. The couplingstructure 120 can assume various forms, and is generally located alongan intermediate portion of the inner shaft assembly 34. In someconstructions, the coupling structure 120 includes one or more fingerssized to be received within corresponding apertures formed by theprosthetic heart valve stent frame (e.g., the prosthetic heart valvestent frame can form wire loops at a proximal end thereof that arereceived over respective ones of the fingers when compressed within thecapsule 40).

The intermediate tube 102 is formed of a flexible polymer material(e.g., PEEK), and is sized to be slidably received within the deliverysheath assembly 36. The proximal tube 104 can include, in someembodiments, a leading portion 122 and a trailing portion 124. Theleading portion 122 serves as a transition between the intermediate andproximal tubes 102, 104 and thus in some embodiments is a flexiblepolymer tubing (e.g., PEEK) having a diameter slightly less than that ofthe intermediate tube 102. The trailing portion 124 has a more rigidconstruction, configured for robust assembly with the handle 38 such asa metal hypotube. Other constructions are also envisioned. For example,in other embodiments, the intermediate and proximal tubes 102, 104 areintegrally formed as a single, homogenous tube or solid shaft.

The delivery sheath assembly 36 includes the capsule 40 and a deliverysheath shaft 130, and defines proximal and distal ends 132, 134. Thecapsule 40 extends distally from the delivery shaft 130, and in someembodiments has a more stiffened construction (as compared to astiffness of the delivery shaft 130) that exhibits sufficient radial orcircumferential rigidity to overtly resist the expected expansive forcesof the stented prosthetic heart valve in the compressed arrangement. Forexample, the delivery shaft 130 can be a polymer tube embedded with ametal braiding, whereas the capsule 40 is a laser-cut metal tube.Alternatively, the capsule 40 and the delivery shaft 130 can have a moreuniform construction (e.g., a continuous polymer tube). Regardless, thecapsule 40 is constructed to compressively retain the stented prostheticheart valve at a predetermined diameter when loaded within the capsule40, and the delivery shaft 130 serves to connect the capsule 40 with thehandle 38. The delivery shaft 130 (as well as the capsule 40) isconstructed to be sufficiently flexible for passage through a patient'svasculature, yet exhibit sufficient longitudinal rigidity to effectuatedesired axial movement of the capsule 40. In other words, proximalretraction of the delivery shaft 130 is directly transferred to thecapsule 40 and causes a corresponding proximal retraction of the capsule40. In other embodiments, the delivery shaft 130 is further configuredto transmit a rotational force or movement onto the capsule 40.

The handle 38 generally includes a housing 140 and one or more actuatormechanisms 142 (referenced generally). The housing 140 maintains theactuator mechanism(s) 142, with the handle 38 configured to facilitatesliding movement of the delivery sheath assembly 36 relative to therecapture assembly 32 and the inner shaft assembly 34, as well as therecapture assembly 32 relative to the inner shaft assembly 34 and thedelivery sheath assembly 36. The housing 140 can have any shape or sizeappropriate for convenient handling by a user. In one simplifiedconstruction, a first, deployment actuator mechanism 142 a includes auser interface or actuator 144 slidably retained by the housing 140 andcoupled to a delivery sheath connector body 146. The proximal end 132 ofthe delivery sheath assembly 36 is connected to the delivery sheathconnector body 146. The inner shaft assembly 34, and in particular theproximal tube 104, is slidably received within a passage 148 (referencedgenerally) of the delivery sheath connector body 146, and is rigidlycoupled to the housing 140. A second, recapture actuator mechanism 142 b(referenced generally) similarly includes a user interface or actuator150 moveably maintained by the housing 140 and coupled to the recaptureassembly 32 via one or more bodies (not shown) facilitating movement ofthe recapture assembly 32 with operation of the recapture actuator 150.With this but one acceptable construction, the deployment actuator 144can be operated to effectuate axial movement of the delivery sheathassembly 36 relative to the recapture assembly 32 and the inner shaftassembly 34. Similarly, the recapture actuator 150 can be manipulated toaxially slide the recapture assembly 32 relative to the inner shaftassembly 34 and the delivery sheath assembly 36.

FIG. 4A illustrates, in simplified form, loading of a stented prostheticheart valve 160 within the delivery system 30. In the loaded state ofFIG. 4A, the prosthetic heart valve 160 is crimped over the inner shaftassembly 34, such that the prosthetic heart valve 160 engages thecoupling structure 120. The capsule 40 compressively contains theprosthetic heart valve 160 and recapture assembly 32 in the compressedarrangement. Finally, the distal end 54 of the recapture assembly 32 islongitudinally spaced from the prosthetic heart valve 160, with theframe 42 assuming the compressed condition described above. For example,with the arrangement of FIG. 4A, the recapture assembly distal end 54 isproximally spaced from the prosthetic heart valve 160. As implicated byFIG. 4A, then, the capsule 40 exhibits sufficient structural integrityto compressively maintain the prosthetic heart valve 160 in thecompressed arrangement without the frame 42, or any other portion of therecapture assembly 32, being disposed over the prosthetic heart valve160 in the loaded state.

To deploy the prosthetic heart valve 160 from the delivery system 30,the delivery sheath assembly 36 is withdrawn from over the prostheticheart valve 160, for example by proximally retracting the capsule 40,such that the capsule distal end 134 is proximal the coupling structure120. Once the capsule 40 is proximal the coupling structure 120, theprosthetic heart valve 160 is allowed to self-expand to a naturalarrangement thereby releasing from the delivery system 30.

In some instances, a clinician may desire to only partially deploy theprosthetic heart valve 160 and then evaluate before fully releasing theprosthetic heart valve 160. For example, the delivery system 30 loadedwith the prosthetic heart valve 160 can be employed as part of a methodto repair a damaged heart valve of a patient. Under these circumstances,the delivery system 30, in the loaded state, is advanced toward thenative heart valve implantation target site, for example in a retrogradeapproach, through a cut-down to the femoral artery and into thepatient's descending aorta. The delivery system 30 is then advanced,under fluoroscopic guidance, over the aortic arch, through the ascendingaorta, and midway across the defective aortic valve (for aortic valvereplacement). Once positioning of the delivery system 30 is estimated,the delivery sheath assembly 36, and in particular the capsule 40, ispartially retracted relative to the prosthetic heart valve 160 as shownin FIG. 4B. A distal region 170 of the prosthesis 160 is thus exteriorlyexposed relative to the capsule 40 and self-expands. In the partiallydeployed arrangement of FIG. 4B, however, at least a proximal region 172of the prosthesis 160 remains within the confines of the capsule 40, andthus coupled to the delivery system 30. In this partially deployedstate, a position of the stented prosthetic heart valve 160 relative tothe desired implantation site can again be evaluated.

In the event the clinician believes, based upon the above evaluation,that the prosthesis 160 should be repositioned relative to theimplantation site, the prosthetic heart valve 160 must first becontracted and “resheathed” by transitioning the delivery system 30 to arecapturing state. As shown in FIG. 4C, the recapture assembly 32 isdistally advanced relative to the delivery sheath assembly 36. Inparticular, the frame 42 and sleeve 50 are distally advanced beyond thedistal end 134 of the capsule 40. Due to the distal advancement of therecapture assembly 32, recapture frame 42 expands, forming the funnelshape 56 with a distally increasing diameter. In particular, the frame42 deflects radially outwardly in response to retraction of the deliverysheath assembly 38 and/or distal advancement of recapture assembly 32.As discussed above, the funnel shape 56 can be formed by frame 42,sleeve 50, capsule 40 and/or combinations thereof. The recaptureassembly is maneuvered into contact with the exposed distal region 170of the prosthetic heart valve 160. The sleeve 50 readily slides along asurface of the prosthetic heart valve 160, with the distal end 54 gentlyengaging the distal region.

Distal advancement of the recapture assembly 32 continues along theprosthetic heart valve 160 as shown in FIG. 4D. While the distal region170 may or may not slightly compress in response to placement within therecapture assembly 32, complete compression of the prosthetic heartvalve 160 does not occur. However, due to the funnel shape 56,compressive forces required to recapture the prosthetic heart valve 160are reduced. As shown in FIG. 5E, the recapture assembly 32 issubsequently distally advanced, forming an enclosed region that can berepositioned and/or retracted.

Once the prosthetic heart valve 160 is recaptured, the delivery system30 can be repositioned relative to the implantation site, and theprocess repeated until the clinician is comfortable with the achievedpositioning. Alternatively, the resheathed stented prosthetic heartvalve 160 can be removed from the patient.

The systems and methods of the present disclosure provide a markedimprovement over previous designs. By providing an expandable recaptureassembly apart from the delivery sheath capsule otherwise utilized tocompressively retain the stented prosthetic heart valve, a partiallydeployed prosthesis is more readily recaptured.

Although the present disclosure has been described with reference topreferred embodiments, workers skilled in the art will recognize thatchanges can be made in form and detail without departing from the spiritand scope of the present disclosure.

1.-24 (canceled)
 25. A method of deploying a stented prosthetic heartvalve to an implantation site, the method comprising the steps of:receiving a delivery system on which an expandable prosthetic heartvalve is provided in a first compressed arrangement within a capsule ofthe delivery system; wherein the delivery system further includes arecapture assembly that is longitudinally spaced apart from theprosthetic heart valve at a position proximal to the prosthetic heartvalve when the prosthetic heart valve is in the first compressedarrangement; delivering the prosthetic heart valve in the compressedarrangement through a bodily lumen of the patient and to theimplantation site via the delivery system; retracting the capsule toallow the prosthetic heart valve to partially expand at the implantationsite; and distally advancing the recapture assembly relative to theprosthetic heart valve such that the prosthetic heart valve transitionsto a second compressed arrangement within the recapture assembly. 26.The method of claim 25, further comprising the step of repositioning theprosthetic heart valve when the prosthetic heart valve is in the secondcompressed arrangement within the recapture assembly.
 27. The method ofclaim 25, further comprising the step of removing the prosthetic heartvalve from the patient when the prosthetic heart valve is in the secondcompressed arrangement within the recapture assembly.
 28. The method ofclaim 25, wherein the recapture assembly includes a recapture frame anda sleeve.
 29. The method of claim 28, wherein the delivery systemincludes an inner shaft assembly over which the capsule is slidablydisposed; wherein the sleeve of the recapture assembly is also slidablydisposed over the inner shaft assembly.
 30. The method of claim 28,wherein the recapture frame includes a wire frame formed of a shapememory material.
 31. The method of claim 28, wherein the recapture frameforms a support structure defining an internal surface and wherein thesleeve is attached to the internal surface.
 32. The method of claim 28,wherein upon retraction of the capsule, a frame of the recaptureassembly transitions to an expanded arrangement.
 33. The method of claim25, further comprising the step of evaluating a position of theprosthetic heart valve relative to the implantation site afterretracting the capsule and distally advancing the recapture assemblyrelative to the prosthetic heart valve such that the recapture assemblyis distal the capsule and expands to an expanded arrangement having adistally increasing diameter.
 34. The method of claim 25, wherein, in aloaded state when the capsule is in the first compressed arrangementwithin the capsule, the recapture assembly is longitudinally displacedfrom the stented prosthetic heart valve.
 35. The method of claim 25,wherein a maximum diameter of the stented prosthetic heart valve in afully expanded arrangement is greater than a maximum diameter of thestented prosthetic heart valve the first compressed arrangement and amaximum diameter of the stented prosthetic heart valve the secondcompressed arrangement.
 36. The method of claim 25, wherein a maximumdiameter of the stented prosthetic heart valve the first compressedarrangement is less than a maximum diameter of the stented prostheticheart valve the second compressed arrangement.
 37. A method of deployinga stented prosthetic heart valve to an implantation site, the methodcomprising: receiving a delivery system loaded with a radiallyexpandable prosthetic heart valve having a stent frame to which a valvestructure is attached, the delivery system including a delivery sheathcapsule containing the prosthetic heart valve in a compressedarrangement over an inner shaft assembly in a loaded state of thesystem, and a recapture assembly including a recapture frame and sleeveslidably disposed over the inner shaft assembly, the recapture assemblybeing longitudinally spaced from the prosthetic heart valve in theloaded state; delivering the prosthetic heart valve in the compressedarrangement through a bodily lumen of the patient and to theimplantation site via the delivery system in the loaded state;proximally retracting the delivery sheath capsule relative to theprosthetic heart valve such that a distal region of the prosthetic heartvalve is exposed distal the capsule, wherein the distal regionself-expands toward a deployed arrangement; evaluating a position of theprosthetic heart valve relative to the implantation site; distallyadvancing the recapture assembly relative to the prosthetic heart valvesuch that the recapture assembly is distal the capsule and expands to anexpanded arrangement having a distally increasing diameter; distallyadvancing the frame over the prosthetic heart valve; arranging therecapture assembly over the prosthetic heart valve to cause the distalregion of the prosthetic heart valve to transition toward the collapsedarrangement within the recapture assembly; and fully proximallyretracting the recapture assembly from the prosthetic heart valve suchthat the prosthetic heart valve self-deploys from the inner shaftassembly.
 38. The method of claim 37, wherein the delivery sheathcapsule is provided as part of a delivery sheath assembly furtherincluding a delivery sheath shaft, and further wherein the recaptureassembly is slidably disposed between the delivery sheath assembly andthe inner shaft assembly.
 39. The method of claim 37, wherein distallyadvancing the recapture assembly includes sliding the recapture assemblyrelative to the delivery sheath assembly.
 40. The method of claim 39,wherein arranging the recapture sheath over the prosthetic heart valveto recapture the prosthetic heart valve includes sliding the frame andsleeve over the prosthetic heart valve.
 41. The method of claim 37,wherein the recapture frame includes a wire frame formed of a shapememory material.
 42. The method of claim 37, wherein the sleeve isformed of a polymeric material.
 43. The method of claim 37, wherein therecapture frame forms a support structure defining an internal surfaceand wherein the sleeve is attached to the internal surface.
 44. Themethod of claim 37, wherein upon retraction of the delivery sheathcapsule relative to the recapture assembly, the recapture frametransitions to the expanded arrangement.